Condition-responsive signalling device



' Nov. 17, 1959 W. A. BERTRAND CONDITION-RESPONSIVE SIGNALLING DEVICE Filed Aug. 26. 1957 INVENTOR. .nl Maze: Alf/P716410,

BYMgM United States Patent 2,913,713 CONDITION-RESPONSIVE SIGNALLING DEVICE Wallace A. Bertrand, Indianapolis, Ind.

Application August 26, 1957, Serial No. 680,086

Claims. or. 340-359) The present invention relates to a condition-responsive signalling mechanism. Systems whereby a codingv signal identifying the current value of a variable condition will be transmitted upon energization of a transmitting circuit, are well known, one example of such a. system being illustrated, for instance, in the patent to Range et al. 2,730,709, issued January 10, 1956.

In such a system, as known heretofore, energization of the signalling mechanism causes a feeler to move, from a position of rest, rectilinearly past a series of proportionately-geared drums, each formed with an axiallyspaced series of ribs of successively increasing peripheral extent, to a remote position, and then rectilinearly in the opposite direction, back to its position of rest. As the feeler travels in one of these directions, it is actuated by the ribs which it encounters on each drum, momentarily to close a signalling circuit, whereby a code will be transmitted, depending upon the relative rotational positions of the several drums; but as it travels in th other direction it is unaffected by such ribs. Thus, a waiting period, usually equal in length to the transmitting period, is introduced into the travel cycle of the signalling mechanism. One form of signalling circuit adapted for use in sucha system is illustrated, for instance, in the patent to Wong 2,802,205, issued August ,6, 1957.

V The primary object of the present invention is to provide, in a generally-similar system, an arrangement of drums concentrically about an axis of revolution through which the feeler travels, whereby a coding cycle will involve one complete revolution of the feeler about such axis, and no such waiting period will be involved.

'Further objects of the invention will appear as the description proceeds. i

To the accomplishment of the above and related objects, my invention may be embodied in the forms illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that change may be made in thespecific constructions illustrated and described, so long as'the scope ofthe appended claims is not violated.

Fig. l is a plan view of a signalling system constructed in accordance with the present invention;

v Fig. 2 is a front elevation thereof, as viewed from below Fig. 1; and

' Fig. 3 is a plan view, similar to Fig. l, but drawn to 60 In the drawings, '1 have shown a base in which is a smaller scale and illustrating modifications.

will include a normally-closed switch 14 which is pro-- vided with an actuating arm preferably carrying a roller disposed in. the path of a trip 16. The construc tion and arrangement of parts aresuch that, so long-as the trip 16 :engages the roller on arm 15, switch 14 will be held open; but when the trip is moved out of contact with said roller, the switch 14 will be closed to maintain energization of the motor -13.

Circuits of this general type are so well known that illustration thereof is deemed to be unnecessary. The switch 14 may be momentarily shorted periodically by a time clock mechanism, or by manual actuation, or by a conventional ringing circuit or in any other well known manner. In any event, it will be understood that, when the energizing circuit for the motor 13 is thus momentarily completed, the shaft 11 will be driven to turn the 9 table 12 in a counter clockwise direction, as seen in mounted upon the table 12 to travel therewith, said switch being connected in a conventional signalling circuit (not shown). The feeler 18 projects beyond the periphery of the disc 12 and is angularly inclined to trail the direction of rotation of the table 12. While I prefer to use a normally-open switch in the signalling circuit, so that, in the manner described hereinafter, thev code will be transmitted by intermittent closures of the signalling circuit, it will be obvious that a normally-closed switch could be used at the point 17 and the code could be transmitted by intermittently breaking the signalling circuit.

Suitably journalled in bearings supported upon the base '10 is a shaft 19 carrying a drum 20, whose external surface is in the form of a surface of revolution obtained by revolving a concave are about the axis of the drum. The drum is so proportioned and located that, in any position of rotation about its own axis, it presents, toward the axis of the shaft 11, a linear surface which lies in a circle concentric with the axis of the shaft 11 and in the plane of travel of the distal end of the feeler 18.

' end of each irregularity 23 is disposed in the same plane radial to the axis of the shaft 11, while the opposite ends of successive irregularities 23 terminate at different distances from said plane. In the illustrated embodiment of the invention, the irregularities 22 and 23 are raised ribs;

in but it will be apparent that, depending upon the particular characteristics of the switch 17, those irregularities could be, instead, grooves let into the peripheral surface of the drum. The essential characteristic of the said irregularities is that, as the free end of the feeler 18 sweeps across the irregularities currently disposed in the plane of travel of the feeler end, the feeler end is caused or permitted to move substantially radially, with respect to the shaft, as it engages each irregularity.

In the illustrated embodiment of the invention, each drum is formed with one peripherally-continuous irregularity and nine substantially-equally spaced discontinu ous irregularities, Thus, if that portion of the peripheral surface of the drum which is spaced in one direction from-the radial plane common to the ends of the ir-.

' regularities"23 is currently located in the plane of travel of the feeler 18, the feeler end will be caused to move in one direction ten times during traversal of the axial length of the drum; if that portion of said surface closely adjacent said radial plane in the opposite direction .is disposed in the plane of travel of the feelen' 'the feeler Patented Nov. 17, 1959.

As is clearly illustrated, one

end will be caused to move only once during such traversal; and if an intermediate portion of said surface is disposed in the plane of travel of the feeler 13, said feeler will be caused 50 to move, during such traversal, a number of times equal to the number of irregularities which extend peripherally to the'current portion of the peripheral surface of the drum.

A beveled gear '24 is fixed to the shaft 19 at a point spacedfrom one end of the drum 2%, and a smaller beveled gear 25 is fixed to said shaftat .a point spaced from theopposite end of the drum. In the illustrated embodiment of the invention, the pitch diameter of the gear 24 is ten timeslthe pitch diameter of the gear25'.

be disposed in the travel path of the feeler to transmit zero for each of drums 20 and 27. It, now, the pressure in the chamber should rise to 1.01 pounds per square inch, the shaft l will be turned through one-hundredth of a revolution in a clockwise direction as viewed in Fig 2. Because of the ratio shown between the gears 24 and 31, the shaft '26 will be turned through one-tenth of a revolution in a clockwise direction as viewed from the right in Fig. 1, thus moving all of the irregularities 30 out of the travel path of the feeler 18. Drums 33 and 4% will be moved so slightly as not to change the eifective positions of their irregularities. 'If, at this point,

p the motor 1-3 is cycled, the feeler 18 will sweep the drum @Asecond shaft 26 is journalled in suitable bearings;

carried by the base iii with its axis angularly related to the axis of the-shaft but disposed in a common plane therewith perpendicular to the axis of the shaft 11. A drum 27 like the drum 2% and formed to dispose a portion 28 of its surface in the same circle in which the drum portion 21 lies, is fixed to the shaft 26 and is formed with a peripherally-continuous irregularity 29 like the irregularity 22 adjacent one end, and with a series of discontinuous irregularities 3Q, like the'i'rregularities 2-3. A gear 31 having a pitch diameter one-tenth as great as the pitch diameter of the gear 24 is fixed to the shaft 26 in meshing relation with the gear 24].

A third shaft 32, having its axis disposed in the plane.

common to the axes of shafts 19 and 26, carries a drum 33 like the drums 23 and 27 and having a surface portion fsd disposed in the circle common to thesurface portions 21 and 28. a peripherally continuous irregularity 35 and a series of discontinuous irregularities 36 similar, respectively, to the irregularity 22 and the irregularities 23. A gear 37 having a pitch diameter ten times that ofthe gear 25 is fixed to the shaft 32 in meshing engagement with the gear 25; and a'gear 38 having a pitch diameter onetenth that of the gear 37 is fixed to the opposite end of the shaft 32.

A fourth shaft 39 is disposed with its axis in, the said common plane and carries a drum 4t? like the drum 2i formed to provide a surface portion 4-1 disposed in the circle common to the surface portions 21, 28 and 34.

- to be put, such means may-be connected to a similar extension of any one of the other shafts 26,32 or 39. Almost any variable condition can be measured by the illu'strated mechanism; but let it be supposed that it is desired to measure pounds per square inch of pressure in a chamber. Any suitable form of pressure-responsive device will be so positioned as to be subjected to variations in such pressure and will be connected, in any suitable way, to turn the shaft 19 through one complete revolution, in one direction or the other, in response to a variation of one pound per square inch, in one direc tion or the other, in the chamber pressure.

Let it be supposed that, according to prearrangement,

ten impulses transmitted from any drum shall be read as zero, one impulse shall be read as,one and so on. Thus, the parts will be so arranged that, when the'pres sure in the chamber is one pound per square inch'gauge, all nine of the irregularities 43 will be disposed in'the travel path of the feeler 18 to transmit zero for drum 40, all of the irregularities -36 will be disposed outof that path'so that irregularity 35 will transmit a single impulse for drum 33, and all of the irregularities 23 and 30 will Said drum further is provided with 40, being moved ten times, as before, by the irregularities 42 and 43, will then sweep the drum 33, being moved only once by the irregularity 35, will then sweep the drum 20, being moved ten times by the irregularities 23 and 22 thereof, will then sweep the drum 27, being moved only oncev by the irregularity 29, and then will come to rest as the trip. 16 actuates the switch arm 15. The code thus transmitted will be interpreted to indicate a chamber pressure of 01.01 pounds per square inch.

If the pressure rises to 2.52 pounds, the shaft 19 will be turned through 2.52 revolutions. Because of the above-described ratios, the parts will come to rest with all of the irregularities 43, the longest of the irregular ities 36, the first four of the irregularities'23 and the longest of theirregmlarities 38 in the travel path of the.

feeler 18; so that, as the feeler 18 moves through its cycle, it will be actuated ten times as it traverses drum 40, to transmit zero, twice as it traverses drum 33, five times as'it traverses drum 2% and twice as it traverses drum 27. The resultant code signal will be interpreted as 02.52.

If the pressure rises to 37.65 pounds per square inch, the shaft 19 will be driven through a corresponding number. of rotations and the parts will come to rest with the first two of the irregularities 43, the first six of the irregularities 36, the first five of the irregularities 2'3 and the first four of the irregularities 36' in the travel path of the feeler 18; so that the feeler, when cycled, will be actuated three times as it traverses drum 4%, seven times as, it traverses drum '33, six times as it traverses drum 20,.

and five times as it traverses drum 27,

In order to simplify the reading of the code, it may be.

desirable to make the axial width of each of the continuous irregularities 22, 29, 35 and 42 greater than that of the discontinuous irregularities.

It will be perceived that, by the present invention, I

have eliminated the time loss, the wear and the power consumption involved in the functionless travel in one direction of a reciprocatory feeler, which cannot be considered to take any desired position in the group of signals; and that, although a decimal system is illustrated, the mechanism can be adapted to any desired system by appropriate changes in the gear ratios and the selection of an appropriate number of irregulaiitieson each drum The signal circuit may, of course, be arranged to trans- Init an audible signal or a visual signal or to operate any desired form of recorder; and transmission of the slgnal to a receiving station may be over wires or by radio. 7

While I have shown a system of drums to transmit signals up to four digits, any desired number of drums through a similar mechanism.

If the mechanism of the present disclosure must be mounted at a distance from the location of the variable condition to be metered, tre shaft 19 may be driven by a Selsyn receiver dominated by a Selsyn transmitter at the site of the variable condition.

If, for instance, it should be desired to transmit, during a cycle of the device, data relating to two or more variable conditions such as, for instance, the pressure and the temperature within a' chamber, a system as suggested in Fig. 3 may be used. In that system, I have shown three drums geared together in a suitable ratio to constitute a group indicated by the reference numeral '50, andjthree other drums "geared together in a suitable ratio and indicated by the'reference numeralSl. The shaft in the group 59 corresponding to the shaft 19 of Fig. 1 might be controlled in response to pressure in the chamber, while the shaft of the group '51 corresponding to the shaft 19 of Fig. 1 might be driven in response to variations in the temperature at the chamber. All of the drums of the two groups being mounted upon axes disposed in a common plane, the feeler 518 would sweep the drums of the first group and then, after a pause, sweep the drums of the second group before coming to a stop, thus transmitting a code representing three digits to indicate pressure and a second code representing three digits to indicate temperature. Obviously, more than two independently-driven groups of drums may be similarly arranged about the axis of the feeler 18, or the number of drums in any group may be increased or reduced.

It will be obvious without further explanation that data relating to variable liquid levels, gas, electric or water meter indications, or positions of machine parts, as well as other types of data might be transmissible through the mechanism disclosed herein.

I claim as my invention:

1.In a device of the class described, a rotor supported for travel about an axis, single switch means mounted on said rotor and having a feeler, said switch means being mounted to move, with said rotor, about said axis, and a plurality of members grouped about said axis substantially at a common distance therefrom, each of said members being mounted to turn about a separate axis and all of said separate axes being disposed substantially in a common plane normal to the axis of said rotor, each of said members being formed to provide an axially-extending surface swept by said feeler as said rotor travels about its own axis, said surface of each such member being formed with an axially-spaced series of irregularities of progressively varying peripheral length, means connected to one of said members to turn the same about its own axis in a direction and to an extent proportionately-responsive to variations in an external condition, and means operatively connecting said one member to turn others of said members, in response to turning movement of said one member, at velocities different from, but bearing predetermined ratios to, the velocity of said one member, said feeler acting, upon encountering and then leaving any one of said irregularities, to actuate said switch means from normal condition to abnormal condition and back to normal condition.

2. In a device of the class described, an electric signal circuit, a rotor supported for travel about an axis, a single switch connected in and dominating said circuit, said switch having a feeler and being mounted to move, with said rotor, about said axis, and a plurality of members grouped about said axis substantially at a common distance therefrom, each of said members being mounted to turn about a separate axis and all of said separate axes being disposed substantially in a common plane normal to the axis of said rotor, each of said members being formed to provide an axially-extending surface swept by said feeler as said rotor travels about its own axis, said surface of each such member being formed with an axially-spaced series of irregularities of progressively varying peripheral length, means connected to one of said members to turn the same about its own axis in a direction and to an extent proportionately-responsive to variations in an external condition, and means operatively connecting said one member to turn others of said members, in response to turning movement of said one member, at velocities different from, but bearing predetermined ratios to, the velocity of said one member, said feeler acting, upon encountering and then leaving any one of said irregularities, to actuate said switch from normal condition to abnormal condition and back to normal condition.

3. In a device of the class described, a rotor supported for travel about an axis, switch means having a single feeler mounted to rnove, with said rotor, about said axis, and a plurality of members grouped about said axis substantially at a common distance therefrom, each of said members being mounted to turn about a separate axisand all of said separate axes being disposed substantially in a common plane normal to the axis of said rotor, each of said members being formed to provide an axially-extending surface swept by said feeler as said rotor travels about its own axis, said surface of each such member being formed with an axially-spaced series of irregularities of progressively varying peripheral length, means connected to one of said members to turn the same about its own axis in a direction and to an extent proportionately-responsive to variations in an external condition, means operatively connecting said one member to turn others of said members, in response to turning movement of said one member, at velocities different from, but bearing predetermined ratios to, the velocity of said one member, means connected to still another of said members to turn the same about its own axis in a direction and to an extent proportionately-responsive to variations in a different external condition, and means operatively connecting said last-named member to turn still others of said members, in response to tuming movement of said last-named member, at velocities different from, but bearing predetermined ratios to, the velocity of said last-named member, said feeler acting, upon encountering and then leaving any one of said irregularities, to actuate said switch from normal condition to abnormal condition and back to normal condition.

4. In a device of the class described, a rotor supported for travel about an axis, switch means having a single feeler mounted to move, with said rotor, about said axis, and a plurality of members grouped about said axis substantially at a common distance therefrom, each of said members being mounted to turn about a separate axis and all of said separate axes being disposed substantially in the plane of travel of said feeler, each of said members being formed to provide an axially-extending surface swept by said feeler as said rotor travels about its own axis, said surface of each such member being formed with an axially-spaced series of irregularities of progressively varying peripheral length, means connected to one of said members to turn the same about its own axis in a direction and to an extent proportionately-responsive to variations in an external condition, and means operatively connecting said one member to turn others of said members, in response to turning movement of said one member, at velocities ditferent from, but bearing predetermined ratios to, the velocity of said one member, said feeler acting, upon encountering and then leaving any one of said irregularities, to actuate said switch from normal condition to abnormal condition and back to normal condition.

5. In a device of the class described, a rotor, electric motor means for driving said rotor, a normally-closed switch in the energizing circuit for said motor and effective, upon momentary opening, to deenergize said circuit and stop said motor, a series of drums grouped about the axis of said rotor, each drum being disposed upon a separate axis to turn thereabout and all of said drum axes being disposed substantially in a common plane normal to said rotor axis, each drum, in every position of rotation about its own axis, presenting in said plane a surface concentric with said rotor axis, and all of said drum surfaces lying in a common circle, each drum further being provided with an axially-spaced series of peripherally-extending ribs, and successive ribs of each such series having progressively increasing peripheral extents, a signal circuit, a normally-open switch mounted to turn with said rotor and having a feeler disposed substantially in said common plane and positioned to sweep said drum surfaces successively as said rotor turns, said ribs, when encountered by said feeler, acting to close said normally-open switch momentarily, means 0p- References Cited in the file of this patent UNITED- STATES PATENTS 2,067,098 7 Rogers JanfS, 1937 2,730,709 Range Jan. (10, 1956 2,802,205 Wong Aug. 6, 1957 

